Lubricant containing cellulose acetate



Patented July 12, 1932 UNITED STATES PATENT OFFICE CYRIL J. STAUD AND JAMES T. FUESS, OF ROCHESTER, NEW YORK, ASSIGNOR S TO EAST- I KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OF NEW YORK LUBRICANT CONTAINING CELLULOSE ACETATE 1T0 Drawing.

This invention relates to a lubricant and more particularly to a lubricating compound containing'acetone soluble cellulose acetate which is adapted to withstand the higher temperatures without breakdown.

' Lubricants are normally made by compounding various high boiling fractions of crude oil. Lubricants are also compounded from vegetable and animal fats or oils but llofto our knowledge no one has ever prepared a lubricant which includes cellulose acetate in its com osition.

We ave found it possible to prepare a lubricant which has the exceptional advan- {lojtage of withstanding the higher temperatures under which lubricants are expected to operate by dissolving cellulose acetate in a mixture of diethyl phthalate and ethyl lactate. As an alternative method of re- 20 paration, the cellulose acetate may be rst moistened with ethyl lactate and then dissolvedby the addition of diethyl phthalate in any suitable quantity. v i

4 The cellulose acetate employed by us is 95 preferably of the acetone soluble variety having an acetyl content ranging between' about 36.5% and 41.5% and having a viscosity in acetone (1 to 4) of anywhere from 5 to "500 seconds as determined by the falling ball method. If the acetone soluble cellulose acetate isto be dissolved directly in the diethyl phthalate-ethyl lactate mixture we employ approximately equal parts of the diethyl phthalate and ethyl lactate in prepar- Il ing the mixture. In any event the proportion of ethyl lactate to diethyl phthalate should not be less than 3 to 7 when dissolv ing the cellulose acetate in the mixture, as ot erwise a good solution of the cellulose acetate will not be obtained.

As an example of the preparation of our novel lubricant we may dissolve 100 parts of acetone soluble cellulose acetate, having 1 an acetyl content of approximately 40% and a viscosity of approximately 100 seconds, in

approximately 300 c. c. of a mixture of about equal parts by volume of diethyl phthalate and ethyl lactate. This will give a lubricant which has sufiicient body for a number of purposes and which will'withstand tempera- Application filed December 24, 1930. Serial No. 504,633.

tures in the neighborhood of 250 to 300 de grees C. without any material breakdown of the lubricant.

As an alternative method of preparation we may moisten 100 1parts of acetone soluble cellulose acetate 0. approximately 40% acetyl value and 100 seconds viscosity, with from -to 75 c. c. of ethyl lactate, following which diethyl phthalate may be added to obtam solution of the cellulose acetate. The striking feature of this alternative is that after the acetone soluble cellulose acetate is once moistened with the ethyl. lactate, the diethyl phthalate may be added in any quantity desired and solution of the cellulose acetate still be obtained. In other words, by first moistening the cellulose acetate with ethyl lactate there may be added diethyl phthalate in an amount which is more than SllfilClBIlt to exceed the ratio 7 parts of diethyl phthalate to3 parts of ethyl lactate. By this procedure diethyl phthalate may merely be added until the composition has the desired viscosity or fluidity.

Another striking thing about our invention is that diethyl phthalate when taken alone is a non-solvent for cellulose acetate,

but when taken with small quantities of ethyl lactate as herein described becomes a solvent 1 for the acetone soluble cellulose acetate and thereby produces a lubricant which has many useful properties.

Obviously the example above given is only and those skilled in the art will readily un-' derstand the adaptation of the invention to the varied conditlons for which any particular lubricant may need to be prepared.

What we claim as our invention and desire to be secured by Letters Patent of the United States is: V

4 1. A lubricant comprising acetone soluble cellulose acetate, diethyl. phthalate and ethyl December, 1930.

ture consisting of approximately equal parts of diethyl phthalate and ethyl lactate.

3. A lubricant comprising approximately parts of acetone soluble cellulose acetate and approximately 200 parts of a mixture consisting of about equal parts of diethyl phthalate and ethyl lactate.

4. A method of preparing a lubricant which comprises moistening acetone soluble cellulose acetate with ethyl lactate and then adding diethyl phthalate in an amount sufficient to dissolve the cellulose acetate.

5. A composition of matter consisting of acetone soluble cellulose acetate, diethyl phthalate and ethyl lactate.

6. A composition of matter consisting of acetone soluble cellulose acetate and a mixture of approximately equal parts of diethyl phthalate and ethyl lactate. 1

Signed at Rochester, N. Y., this 15th day of CYRIL J. STAUD. JAMES 'r. FUESS. 

